1. Field of the Invention
The present invention is directed to systems, processes, methodologies, apparatus and related software for transmission of Internet Protocol data streams over various types of networks. More particularly, the invention relates to the field of encapsulation and insertion of Internet Protocol data streams for transmission over non-IP networks. Accordingly, the general objects of the invention are to provide novel systems, methods, apparatus and software of such character.
2. Description of the Related Art
Broadband media convergence between video, audio and data creates a chaotic environment of different standards and legacy communications technologies. For example, modem digital communications systems are now being used to bundle together video, audio and other types of data each of which may be generated and manipulated in a different data format. One common example of this type of data bundling is voice over IP in which an audio signal of a relatively narrow bandwidth is transmitted together with a synchronized but independent Internet Protocol (IP) data signal so that both can be simultaneously received and used by a signal recipient. It is also becoming more common to package video and audio with IP data for synchronized transmission. For example, it may be desired to merge video and audio signals created in accordance with an MPEG standard with IP data and simultaneously deliver these signals to one or more targeted recipients via the Internet. However, transmission of one or more varying types of data in accordance with a single data transmission protocol presents special difficulties not previously present.
One difficulty associated with encapsulation of IP data streams lies in the fact that IP data streams may be broadcast, unicast or multicast over a given network, again, at the discretion of the user. IP data encapsulation of multicast data streams is particularly difficult to multiplex and re-route over a global communications network. This is because computers that are not the targeted recipients of the multicast streams, cannot recognize the data stream. Therefore, these non-targeted computers also cannot re-route or otherwise process the data stream. Prior attempts have been made to circumvent this difficulty. These efforts have generally involved conversion of a particular multicast IP data stream into a plurality of unicast IP data streams and then transmission of the newly created unicast data streams. While this technique has been marginally successful, it suffers from the deficiency that substantial processing of the data streams must occur on the receiving end of the signal in order to recover the original content. This is especially true in systems that permit the inclusion of multiple IP data packets (each with an associated DSM-CC header) in a single MPEG packet where the IP data packets are smaller than the MPEG packets. This is because, in such systems, each MPEG packet must be searched in its entirety to determine if multiple IP data packets have been packaged into a single MPEG packet and, if so, how many.
There is, accordingly, a need in the art for novel methods, systems and apparatus that are capable of conveniently and efficiently encapsulating and inserting IP data into MPEG data streams in a manner that permits rapid and simple recovery of the original content after reception. Such methods and apparatus should be able to transmit IP data to one or more targeted recipients in an MPEG format regardless of whether the original IP data is broadcast, unicast or multicast. Such methods and apparatus should also be able to transmit IP data in an MPEG format in accordance with either DVB or ATSC formats at the discretion of the user. Such methods and apparatus should further be combined with other broadband communications functions and apparatus such that a single multifunction device can perform a wide variety of functions such as data routing, ad insertion, signal and system monitoring, etc.